Thermally conductive phase change materials

1. A composition comprising: A) about 4 to about 10% based on the weight of the composition of a matrix comprising an organofunctional silicone wax; B) about 90 to about 96% based on the weight of the composition of a thermally conductive filler; C) about 0.05% to about 5% based on the weight of the composition of a treating agent, where component C) comprises an alkoxysilane having the formula: R 5 X Si(OR 6 ) (4 x) , where R 5 is a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atoms and up to about 50 carbon atoms, each R 6 is independently an unsubstituted, saturated hydrocarbon group of at least about 1 carbon atom and up to about 4 carbon atoms, and x is 1, 2, or 3; optionally D) an antioxidant; optionally E) an inhibitor; and at least one component selected from F) an organic wax, a polymer compatible with the organofunctional silicone wax, a hardener, or a combination thereof; G) a vehicle; H) a wetting agent; I) an opacifying agent; J) an antifoaming agent; K) a pigment; L) a flame retardant; M) a spacer; N) a reinforcing filler; and a combination thereof.

2. A composition comprising: A) a matrix comprising an organofunctional silicone wax; B) a thermally conductive filler; C) about 0.05% to about 5% based on the weight of the composition of a treating agent, where component C) comprises an alkoxysilane having the formula: R 5 X Si(OR 6 ) (4 X) , where R 5 is a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atoms and up to about 50 carbon atoms, each R 6 is independently an unsubstituted, saturated hydrocarbon group of at least about 1 carbon atom and up to about 4 carbon atoms, and x is 1, 2, or 3; optionally D) an antioxidant; optionally E) an inhibitor; and at least one component selected from F) an organic wax, a polymer compatible with the organofunctional silicone wax, a hardener, or a combination thereof; G) a vehicle; H) a wetting agent; I) an opacifying agent; J) an antifoaming agent; K) a pigment; L) a flame retardant; M) a spacer; N) a reinforcing filler; and a combination thereof; with the provisos that the organofunctional silicone wax comprises an uncrosslinked organofunctional silicone wax, a crosslinked organofunctional silicone wax, or a combination thereof; where the uncrosslinked organofunctional silicone wax comprises a wax of the formula R 2 R 3 2 SiO(R 3 2 SiO) y (R 3 R 1 SiO) z SiFR 3 2 R 2 , a cyclic wax of the formula (R 3 2 SiO) m (R 3 R 1 SiO) n , or a combination thereof; where each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 24 carbon atoms, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 3 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atom up to about 4 carbon atoms, m is greater than or equal to 0, n is greater than or equal to about 1, with the proviso that m n is up to about 8, y is 0 to about 200, and z is about 1 to about 200, the crosslinked organofunctional silicone wax comprises a reaction product of a) a crosslinking agent comprising an alpha-, omega-diene, an 1-alkenyl-functional organopolysiloxane having at least two 1-alkenyl groups per molecule, or a combination thereof; b) an alpha-olefin; and c) a siloxane having silicon-bonded hydrogen atoms or an organosiloxane having silicon-bonded hydrogen atoms.

3. A composition comprising: A) about 4 to about 10% based on the weight of the composition of a matrix comprising an organofunctional silicone wax, B) about 90 to about 96% based on the weight of the composition of a thermally conductive filler, optionally C) a treating agent, D) about 0.001% to about 1% based on the weight of the composition of an antioxidant, and optionally E) an inhibitor; with the proviso that component D) comprises a phenolic antioxidant or a combination of a phenolic antioxidant and a stabilizer.

4. A composition comprising: A) a matrix comprising an organofunctional silicone wax, B) a thermally conductive filler, optionally C) a treating agent, D) an antioxidant, and optionally E) an inhibitor, with the provisos that the organofunctional silicone wax comprises an uncrosslinked organofunctional silicone wax, a crosslinked organofunctional silicone wax, or a combination thereof; where the uncrosslinked organofunctional silicone wax comprises a wax of the formula R 2 R 3 2 SiO(R 3 2 SiO) y (R 3 R 1 SiO) z SiR 3 2 R 2 , a cyclic wax of the formula (R 3 2 SiO) m (R 3 R 1 SiO) n , or a combination thereof; where each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 24 carbon atoms, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 3 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atom up to about 4 carbon atoms, m is greater than or equal to 0, n is greater than or equal to about 1, with the proviso that m n is up to about 8, y is 0 to about 200, and z is about 1 to about 200, the crosslinked organofunctional silicone wax comprises a reaction product of a) a crosslinking agent comprising an alpha-, omega-diene, an 1-alkenyl-functional organopolysiloxane having at least two 1-alkenyl groups per molecule, or a combination thereof; b) an alpha-olefin; and c) a siloxane having silicon-bonded hydrogen atoms or an organosiloxane having silicon-bonded hydrogen atoms; component D) is present in an amount of at least about 0.001% up to about 1% based on the weight of the composition, and component D) comprises a phenolic antioxidant or a combination of a phenolic antioxidant and a stabilizer.

5. An interface material comprising: I) a composition comprising: A) about 4 to about 10% based on the weight of the composition of a matrix comprising an organofunctional silicone wax, B) about 90 to about 96% based on the weight of the composition of a thermally conductive filler, optionally C) a treating agent, optionally D) an antioxidant, and optionally E) an inhibitor; and II) a substrate; where the composition is coated on two sides of the substrate, and where the substrate comprises a metal foil, a perforated metal foil, a polyamide sheet, a polyethylene terephthalate polyester sheet.

6. An interface material comprising: I) a composition comprising: A) a matrix comprising an organofunctional silicone wax, B) a thermally conductive filler, optionally C) a treating agent, optionally D) an antioxidant, and optionally E) an inhibitor, with the provisos that the organofunctional silicone wax comprises an uncrosslinked organofunctional silicone wax, a crosslinked organofunctional silicone wax, or a combination thereof; where the uncrosslinked organofunctional silicone wax comprises a wax of the formula R 2 R 3 2 SiO(R 3 2 SiO) y (R 3 R 1 SiO) z SiR 3 2 R 2 , a cyclic wax of the formula (R 3 2 SiO) m (R 3 R 1 SiO) n , or a combination thereof; where each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 24 carbon atoms, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 3 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atom up to about 4 carbon atoms, m is greater than or equal to 0, n is greater than or equal to about 1, with the proviso that m n is up to about 8, y is 0 to about 200, and z is about 1 to about 200, the crosslinked organofunctional silicone wax comprises a reaction product of a) a crosslinking agent comprising an alpha-, omega-diene, an 1-alkenyl-functional organopolysiloxane having at least two 1-alkenyl groups per molecule, or a combination thereof; b) an alpha-olefin; and c) a siloxane having silicon-bonded hydrogen atoms or an organosiloxane having silicon-bonded hydrogen atoms; and II) a substrate; where the composition is coated on two sides of the substrate, and where the substrate comprises a metal foil, a perforated metal foil, a polyamide sheet, a polyimide sheet, or a polyethylene terephthalate polyester sheet.

7. An interface material comprising: I) a composition formed as a flat member, a hemispherical nubbin, a convex member, a pyramid, or a cone, where the composition comprises A) about 4 to about 10% based on the weight of the composition of a matrix comprising an organofunctional silicone wax; B) about 90 to about 96% based on the weight of the composition of a thermally conductive filler; optionally C) a treating agent; optionally D) an antioxidant; optionally E) an inhibitor; and at least one component selected from F) an organic wax, a polymer compatible with the organofunctional silicone wax, a hardener, or a combination thereof; G) a vehicle; H) a wetting agent; I) an opacifying agent; J) an antifoaming agent; K) a pigment; L) a flame retardant; M) a spacer; N) a reinforcing filler; and a combination thereof; II) a substrate, where the composition is coated on the substrate; and III) a release sheet covering a surface of the composition opposite the substrate.

8. An interface material comprising: I) a composition formed as a flat member, a hemispherical nubbin, a convex member, a pyramid, or a cone, where the composition comprises A) a matrix comprising an organofunctional silicone wax; B) a thermally conductive filler; optionally C) a treating agent; optionally D) an antioxidant; optionally E) an inhibitor; and at least one component selected from F) an organic wax, a polymer compatible with the organofunctional silicone wax, a hardener, or a combination thereof; G) a vehicle; H) a wetting agent; I) an opacifying agent; J) an antifoaming agent; K) a pigment; L) a flame retardant; M) a spacer; N) a reinforcing filler; and a combination thereof; with the provisos that the organofunctional silicone wax comprises an uncrosslinked organofunctional silicone wax, a crosslinked organofunctional silicone wax, or a combination thereof; where the uncrosslinked organofunctional silicone wax comprises a wax of the formula R 2 R 3 2 SiO(R 3 2 SiO) y (R 3 R 1 SiO) y SiR 3 2 R 2 , a cyclic wax of the formula (R 3 2 SiO) m (R 3 R 1 SiO) n , or a combination thereof; where each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 24 carbon atoms, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 3 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atom up to about 4 carbon atoms m is greater than or equal to 0, n is greater than or equal to about 1, with the proviso that m n is up to about 8, y is 0 to about 200, and z is about 1 to about 200, the crosslinked organofunctional silicone wax comprises a reaction product of a) a crosslinking agent comprising an alpha-, omega-diene, an 1-alkenyl-functional organopolysiloxane having at least two 1-alkenyl groups per molecule, or a combination thereof; b) an alpha-olefin: and c) a siloxane having silicon-bonded hydrogen atoms or an organosiloxane having silicon-bonded hydrogen atoms; II) a substrate, where the composition is coated on the substrate; and III) a release sheet covering a surface of the composition opposite the substrate.

9. A method comprising: i) interposing, along a thermal path between a heat source and a heat spreader, a composition comprising A) about 4 to about 10% based on the weight of the composition of a matrix comprising an organofunctional silicone wax, B) about 90 to about 96% based on the weight of the composition of a thermally conductive filler, optionally C) a treating agent, optionally D) an antioxidant, and optionally E) an inhibitor, ii) heating the composition to a temperature equal to or greater than phase change temperature of the composition, and iii) applying pressure to the composition.

10. The method of claim 9 , further comprising: iv) cooling the composition to a temperature less than the phase change temperature.

11. A method comprising: i) interposing, along a thermal path between a heat source and a heat spreader, a composition comprising: A) a matrix comprising an organofunctional silicone wax, B) a thermally conductive filler, optionally C) a treating agent, optionally D) an antioxidant, and optionally E) an inhibitor, with the provisos that the organofunctional silicone wax comprises an uncrosslinked organofunctional silicone wax, a crosslinked organofunctional silicone wax, or a combination thereof; where the uncrosslinked organofunctional silicone wax comprises a wax of the formula R 2 R 3 2 SiO(R 3 2 SiO) y (R 3 R 1 SiO) z SiR 3 2 R 2 , a cyclic wax of the formula (R 3 2 SiO) m (R 3 R 1 SiO) n , or a combination thereof; where each R 1 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 24 carbon atoms, each R 2 is independently a substituted or unsubstituted monovalent hydrocarbon group, each R 3 is independently a substituted or unsubstituted monovalent hydrocarbon group of at least about 1 carbon atom up to about 4 carbon atoms, m is greater than or equal to 0, n is greater than or equal to about 1, with the proviso that m n is up to about 8, y is 0 to about 200, and z is about 1 to about 200, the crosslinked organofunctional silicone wax comprises a reaction product of a) a crosslinking agent comprising an alpha-, omega-diene, an 1-alkenyl-functional organopolysiloxane having at least two 1-alkenyl groups per molecule, or a combination thereof; b) an alpha-olefin; and c) a siloxane having silicon-bonded hydrogen atoms or an organosiloxane having silicon-bonded hydrogen atoms, ii) heating the composition to a temperature equal to or greater than phase change temperature of the composition, and iii) applying pressure to the composition.

12. The method of claim 11 , further comprising: iv) cooling the composition to a temperature less than the phase change temperature.